1. Field of the Invention
This invention relates to methods of making webs including antenna webs and RFID transponder webs and to RFID antenna webs.
2. Brief Description of the Prior Art
The following prior art is made of record: U.S. Pat. No. 4,910,499 and published U.S. Patent Application 2004/0215350A1.
In the field of radio frequency identification (RFID) to which this invention relates, an RFID chip is connected to an antenna to form a transponder into which data can be written and from which data can be read. It is known to make labels, tags, business forms, packaging and the like which incorporate such transponders. The chips are very small and require connection to antennas. To facilitate this connection, straps including chips are connected to the antennas. A strap includes an RFID chip and a pair of strap contacts or connecting elements used to connect the chip to an antenna. It is common to provide the straps in a wide web, wherein the straps are arranged close to each other in parallel columns and transversely extending rows. These wide strap webs have some residual adhesive on their electrically conductive side resulting from the manufacturing process and accordingly these wide strap webs are co-wound with an adhesive. The straps have a high density along and across the web. In order to use the narrow webs of straps, the straps must eventually be separated as by cutting them from the narrow strap web prior to connection to antennas. Alternately, an electrically conductive tape can be co-wound with the strap web.
It is known to use an electrically conductive thermoset adhesive film to interconnect flexible circuits to printed circuit boards or other flexible circuits. Conductive particles loaded into the adhesive allow interconnection through the adhesive thickness but are spaced far enough apart to be electrically insulating in the plane of the adhesive.